What absorbs at 1761 cm⁻¹ in an FTIR spectrum?
A band near 1761 cm⁻¹ can point to several functional groups. Below are the most likely assignments, ranked by how much published evidence supports each — every one traceable to literature (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 4 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Methacrylate | 2 | 1 | 1.0 |
| Ketone | 2 | 1 | 1.0 |
| Ester | 2 | 1 | 1.0 |
| Carboxyl (COOH) | 2 | 1 | 1.0 |
| Carbonyl (C=O) | 2 | 1 | 1.0 |
| Amide | 2 | 1 | 1.0 |
| Acetate | 2 | 1 | 1.0 |
| Alkyl C-H | 1 | 1 | 1.0 |
| Anhydride | 1 | 1 | 1.0 |
| Alkene (C=C) | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Alkene (C=C) confidence 1.0
“The evidences of grafting and homopolymerisation reactions were supported by the presence of specific absorption peak of carbonyl (>C=O) cm-1, and the absence of absorption peak of maleic double bond (>C=C<) group of maleic anhydride at 176”
Characteristics of maleic anhydrida-modified polystyrene containing sand aggregate DOI: 10.1063/5.0015713 -
Alkyl C-H confidence 1.0
“cm-1 (O-H stretching), 3505 (O-H stretching), at 3648 cm-1 cm-1 (C-H stretching), 2996 (C-H stretching), 1761 2946 Fig.”
Enhanced efficacy of clindamycin hydrochloride encapsulated in PLA/PLGA based nanoparticle system for oral delivery DOI: 10.1049/iet-nbt.2015.0021 -
Acetate confidence 1.0
“Three bands at 1761, 1746, and 1732 appear in the spectra observed in the regions of C=O vibrations (1800-1650 cm-1)-Figure 5B and H-C=O vibraduring ethanol flow in the presence of the catalysts studied.”
Activation of Ethanol Transformation on Copper-Containing SBA-15 and MnSBA-15 Catalysts by the Presence of Oxygen in the Reaction Mixture DOI: 10.3390/ijms24032252 -
confidence 0.9
“Asp-85 band”
Dioumaev 和 Lanyi - 2008 - Switch from conventional to distributed kinetics i DOI: 10.1021/bi801247e.
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